void ntlm_rc4k(BYTE* key, int length, BYTE* plaintext, BYTE* ciphertext)
{
WINPR_RC4_CTX* rc4 = winpr_RC4_New(key, 16);
if (rc4)
{
winpr_RC4_Update(rc4, length, plaintext, ciphertext);
winpr_RC4_Free(rc4);
}
}
BOOL license_send_platform_challenge_response_packet(rdpLicense* license)
{
wStream* s;
int length;
BYTE* buffer;
WINPR_RC4_CTX* rc4;
BYTE mac_data[16];
BOOL status;
DEBUG_LICENSE("Sending Platform Challenge Response Packet");
s = license_send_stream_init(license);
license->EncryptedPlatformChallenge->type = BB_DATA_BLOB;
length = license->PlatformChallenge->length + HWID_LENGTH;
buffer = (BYTE*) malloc(length);
if (!buffer)
return FALSE;
CopyMemory(buffer, license->PlatformChallenge->data, license->PlatformChallenge->length);
CopyMemory(&buffer[license->PlatformChallenge->length], license->HardwareId, HWID_LENGTH);
status = security_mac_data(license->MacSaltKey, buffer, length, mac_data);
free(buffer);
if (!status)
return FALSE;
rc4 = winpr_RC4_New(license->LicensingEncryptionKey,
LICENSING_ENCRYPTION_KEY_LENGTH);
if (!rc4)
return FALSE;
buffer = (BYTE*) malloc(HWID_LENGTH);
if (!buffer)
return FALSE;
status = winpr_RC4_Update(rc4, HWID_LENGTH, license->HardwareId, buffer);
winpr_RC4_Free(rc4);
if (!status)
{
free(buffer);
return FALSE;
}
license->EncryptedHardwareId->type = BB_DATA_BLOB;
license->EncryptedHardwareId->data = buffer;
license->EncryptedHardwareId->length = HWID_LENGTH;
#ifdef WITH_DEBUG_LICENSE
WLog_DBG(TAG, "LicensingEncryptionKey:");
winpr_HexDump(TAG, WLOG_DEBUG, license->LicensingEncryptionKey, 16);
WLog_DBG(TAG, "HardwareId:");
winpr_HexDump(TAG, WLOG_DEBUG, license->HardwareId, HWID_LENGTH);
WLog_DBG(TAG, "EncryptedHardwareId:");
winpr_HexDump(TAG, WLOG_DEBUG, license->EncryptedHardwareId->data, HWID_LENGTH);
#endif
return license_write_platform_challenge_response_packet(license, s, mac_data) &&
license_send(license, s, PLATFORM_CHALLENGE_RESPONSE);
}
void ntlm_init_rc4_seal_states(NTLM_CONTEXT* context)
{
if (context->server)
{
context->SendSigningKey = context->ServerSigningKey;
context->RecvSigningKey = context->ClientSigningKey;
context->SendSealingKey = context->ClientSealingKey;
context->RecvSealingKey = context->ServerSealingKey;
context->SendRc4Seal = winpr_RC4_New(context->ServerSealingKey, 16);
context->RecvRc4Seal = winpr_RC4_New(context->ClientSealingKey, 16);
}
else
{
context->SendSigningKey = context->ClientSigningKey;
context->RecvSigningKey = context->ServerSigningKey;
context->SendSealingKey = context->ServerSealingKey;
context->RecvSealingKey = context->ClientSealingKey;
context->SendRc4Seal = winpr_RC4_New(context->ClientSealingKey, 16);
context->RecvRc4Seal = winpr_RC4_New(context->ServerSealingKey, 16);
}
}
BOOL license_decrypt_platform_challenge(rdpLicense* license)
{
BOOL rc;
WINPR_RC4_CTX* rc4;
license->PlatformChallenge->data = (BYTE *)malloc(license->EncryptedPlatformChallenge->length);
if (!license->PlatformChallenge->data)
return FALSE;
license->PlatformChallenge->length = license->EncryptedPlatformChallenge->length;
if ((rc4 = winpr_RC4_New(license->LicensingEncryptionKey,
LICENSING_ENCRYPTION_KEY_LENGTH)) == NULL)
return FALSE;
rc = winpr_RC4_Update(rc4, license->EncryptedPlatformChallenge->length,
license->EncryptedPlatformChallenge->data,
license->PlatformChallenge->data);
winpr_RC4_Free(rc4);
return rc;
}
BOOL rdp_server_establish_keys(rdpRdp* rdp, wStream* s)
{
BYTE* client_random = NULL;
BYTE* crypt_client_random = NULL;
UINT32 rand_len, key_len;
UINT16 channel_id, length, sec_flags;
BYTE* mod;
BYTE* priv_exp;
BOOL ret = FALSE;
if (!rdp->settings->UseRdpSecurityLayer)
{
/* No RDP Security. */
return TRUE;
}
if (!rdp_read_header(rdp, s, &length, &channel_id))
{
WLog_ERR(TAG, "invalid RDP header");
return FALSE;
}
if (!rdp_read_security_header(s, &sec_flags))
{
WLog_ERR(TAG, "invalid security header");
return FALSE;
}
if ((sec_flags & SEC_EXCHANGE_PKT) == 0)
{
WLog_ERR(TAG, "missing SEC_EXCHANGE_PKT in security header");
return FALSE;
}
rdp->do_crypt_license = (sec_flags & SEC_LICENSE_ENCRYPT_SC) != 0 ? TRUE : FALSE;
if (Stream_GetRemainingLength(s) < 4)
return FALSE;
Stream_Read_UINT32(s, rand_len);
/* rand_len already includes 8 bytes of padding */
if (Stream_GetRemainingLength(s) < rand_len)
return FALSE;
key_len = rdp->settings->RdpServerRsaKey->ModulusLength;
client_random = malloc(key_len);
if (!client_random)
return FALSE;
if (rand_len != key_len + 8)
{
WLog_ERR(TAG, "invalid encrypted client random length");
goto end;
}
crypt_client_random = calloc(1, rand_len);
if (!crypt_client_random)
goto end;
Stream_Read(s, crypt_client_random, rand_len);
mod = rdp->settings->RdpServerRsaKey->Modulus;
priv_exp = rdp->settings->RdpServerRsaKey->PrivateExponent;
crypto_rsa_private_decrypt(crypt_client_random, rand_len - 8, key_len, mod, priv_exp, client_random);
/* now calculate encrypt / decrypt and update keys */
if (!security_establish_keys(client_random, rdp))
goto end;
rdp->do_crypt = TRUE;
if (rdp->settings->EncryptionMethods == ENCRYPTION_METHOD_FIPS)
{
rdp->fips_encrypt = winpr_Cipher_New(WINPR_CIPHER_DES_EDE3_CBC,
WINPR_ENCRYPT,
rdp->fips_encrypt_key,
fips_ivec);
if (!rdp->fips_encrypt)
{
WLog_ERR(TAG, "unable to allocate des3 encrypt key");
goto end;
}
rdp->fips_decrypt = winpr_Cipher_New(WINPR_CIPHER_DES_EDE3_CBC,
WINPR_DECRYPT,
rdp->fips_decrypt_key,
fips_ivec);
if (!rdp->fips_decrypt)
{
WLog_ERR(TAG, "unable to allocate des3 decrypt key");
goto end;
}
rdp->fips_hmac = calloc(1, sizeof(WINPR_HMAC_CTX));
if (!rdp->fips_hmac)
{
WLog_ERR(TAG, "unable to allocate fips hmac");
goto end;
}
ret = TRUE;
goto end;
}
rdp->rc4_decrypt_key = winpr_RC4_New(rdp->decrypt_key, rdp->rc4_key_len);
rdp->rc4_encrypt_key = winpr_RC4_New(rdp->encrypt_key, rdp->rc4_key_len);
if (!rdp->rc4_decrypt_key || rdp->rc4_encrypt_key)
goto end;
ret = TRUE;
end:
free(crypt_client_random);
free(client_random);
if (!ret)
{
winpr_Cipher_Free(rdp->fips_encrypt);
winpr_Cipher_Free(rdp->fips_decrypt);
winpr_RC4_Free(rdp->rc4_encrypt_key);
winpr_RC4_Free(rdp->rc4_decrypt_key);
rdp->fips_encrypt = NULL;
rdp->fips_decrypt = NULL;
rdp->rc4_encrypt_key = NULL;
rdp->rc4_decrypt_key = NULL;
}
return ret;
}
static BOOL rdp_client_establish_keys(rdpRdp* rdp)
{
BYTE* mod;
BYTE* exp;
wStream* s;
UINT32 length;
UINT32 key_len;
int status = 0;
BOOL ret = FALSE;
rdpSettings* settings;
BYTE* crypt_client_random = NULL;
settings = rdp->settings;
if (!settings->UseRdpSecurityLayer)
{
/* no RDP encryption */
return TRUE;
}
/* encrypt client random */
free(settings->ClientRandom);
settings->ClientRandomLength = CLIENT_RANDOM_LENGTH;
settings->ClientRandom = malloc(settings->ClientRandomLength);
if (!settings->ClientRandom)
return FALSE;
winpr_RAND(settings->ClientRandom, settings->ClientRandomLength);
key_len = settings->RdpServerCertificate->cert_info.ModulusLength;
mod = settings->RdpServerCertificate->cert_info.Modulus;
exp = settings->RdpServerCertificate->cert_info.exponent;
/*
* client random must be (bitlen / 8) + 8 - see [MS-RDPBCGR] 5.3.4.1
* for details
*/
crypt_client_random = calloc(1, key_len + 8);
if (!crypt_client_random)
return FALSE;
crypto_rsa_public_encrypt(settings->ClientRandom, settings->ClientRandomLength, key_len, mod, exp, crypt_client_random);
/* send crypt client random to server */
length = RDP_PACKET_HEADER_MAX_LENGTH + RDP_SECURITY_HEADER_LENGTH + 4 + key_len + 8;
s = Stream_New(NULL, length);
if (!s)
{
WLog_ERR(TAG, "Stream_New failed!");
goto end;
}
rdp_write_header(rdp, s, length, MCS_GLOBAL_CHANNEL_ID);
rdp_write_security_header(s, SEC_EXCHANGE_PKT | SEC_LICENSE_ENCRYPT_SC);
length = key_len + 8;
Stream_Write_UINT32(s, length);
Stream_Write(s, crypt_client_random, length);
Stream_SealLength(s);
status = transport_write(rdp->mcs->transport, s);
Stream_Free(s, TRUE);
if (status < 0)
goto end;
rdp->do_crypt_license = TRUE;
/* now calculate encrypt / decrypt and update keys */
if (!security_establish_keys(settings->ClientRandom, rdp))
goto end;
rdp->do_crypt = TRUE;
if (settings->SaltedChecksum)
rdp->do_secure_checksum = TRUE;
if (settings->EncryptionMethods == ENCRYPTION_METHOD_FIPS)
{
rdp->fips_encrypt = winpr_Cipher_New( WINPR_CIPHER_DES_EDE3_CBC,
WINPR_ENCRYPT,
rdp->fips_encrypt_key,
fips_ivec);
if (!rdp->fips_encrypt)
{
WLog_ERR(TAG, "unable to allocate des3 encrypt key");
goto end;
}
rdp->fips_decrypt = winpr_Cipher_New(WINPR_CIPHER_DES_EDE3_CBC,
WINPR_DECRYPT,
rdp->fips_decrypt_key,
fips_ivec);
if (!rdp->fips_decrypt)
{
WLog_ERR(TAG, "unable to allocate des3 decrypt key");
goto end;
}
rdp->fips_hmac = calloc(1, sizeof(WINPR_HMAC_CTX));
if (!rdp->fips_hmac)
{
WLog_ERR(TAG, "unable to allocate fips hmac");
goto end;
}
ret = TRUE;
goto end;
}
rdp->rc4_decrypt_key = winpr_RC4_New(rdp->decrypt_key, rdp->rc4_key_len);
rdp->rc4_encrypt_key = winpr_RC4_New(rdp->encrypt_key, rdp->rc4_key_len);
if (!rdp->rc4_decrypt_key || !rdp->rc4_encrypt_key)
goto end;
ret = TRUE;
end:
free(crypt_client_random);
if (!ret)
{
winpr_Cipher_Free(rdp->fips_decrypt);
winpr_Cipher_Free(rdp->fips_encrypt);
winpr_RC4_Free(rdp->rc4_decrypt_key);
winpr_RC4_Free(rdp->rc4_encrypt_key);
rdp->fips_decrypt = NULL;
rdp->fips_encrypt = NULL;
rdp->rc4_decrypt_key = NULL;
rdp->rc4_encrypt_key = NULL;
}
return ret;
}
